On Mon, Jul 17, 2017 at 01:39:13PM +0200, Peter Krempa wrote: > On Mon, Jul 17, 2017 at 07:27:24 -0400, sferdjao@xxxxxxxxxx wrote: > > From: Sahid Orentino Ferdjaoui <sahid.ferdjaoui@xxxxxxxxxx> > > > > In version 2.7.0, QEMU introduced support of busy polling for > > vhost-net [0]. To avoid paraphrasing original authors of that feature > > and the purpose it I prefer to share a pointer [1]. > > > > This patch serie exposes throught the NIC driver-specific element a > > new option 'poll_us'. That option is only available with the backend > > driver 'vhost' and that because libvirt automatically fallback to QEMU > > if the driver is not specified where that option is not available. > > > > The option 'poll_us' takes a positive. 0 means that the option > > is not going to be exposed. > > We had a similar attempt to do this for disk polling, but that was > rejected since it's not very straightforward for the users to tune this > variable. I think this falls into the same category. > > Here's the discussion for iothread polling: > > https://www.redhat.com/archives/libvir-list/2017-February/msg01048.html Yes, thanks for pointing that out. I do have the same objections to this patch, as for the previous disk polling patch. I just don't think they are practical for a appliction to use - they're too low level to expose to sysadmins, and there's no obvious way for an application to pick the right settings automatically. So I think we're best served by letting QEMU pick defaults Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :| -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list
